ASNT Radiographic Testing Practice Test 2025 - Free Nondestructive Testing Practice Questions and Study Guide

The most commonly used target material in an x-ray tube is tungsten. This is primarily due to its high atomic number, which enhances its efficiency in producing x-rays when bombarded by high-energy electrons. The high atomic number also contributes to a higher radiation yield and better image contrast, essential qualities in radiographic imaging.

Additionally, tungsten has a high melting point (around 3,422 degrees Celsius), making it suitable for withstanding the extreme heat generated during the x-ray production process. Other materials, such as gold or silver, while they do have high atomic numbers, do not possess the same level of thermal stability required for the continuous operation of x-ray tubes. Aluminum, while used in some x-ray applications, is not ideal for target material due to its lower atomic number and inadequate heat resistance compared to tungsten. Overall, tungsten's combination of high atomic number, thermal stability, and efficient x-ray production makes it the preferred choice for x-ray tube targets.